US5601088A
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Systems and methods for filtering artifacts from composite signals
Assignee: EP Technologies Inc
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Filing: 1995-02-17
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Granted: 1997-02-11
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Expires: 2015-02-17
Abstract
Abstract Analog or digital systems and methods filter an artifact from a composite signal, which comprises sample values arranged with respect to time. The systems and methods select sets of WL sample values in time-sequence along the composite signal and arrange the WL sample values of each set into ordered positions following a predetermined permutation. The systems and methods select one of the ordered positions, z, within each permutation. The systems and methods generate a filter output comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the composite signal. The systems and methods remove artifacts from signals derived from a biological event; for example, electrograms, electrocardiograms, electroencephalograms, electrogastrograms, electromyograms, and respiratory signals.
Inventors
- 👤 David K. Swanson
- 👤 Dorin Panescu
- 👤 James G. Whayne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:30
CPC Classifications
H; H03; H03H; H03H17/00; H03H17/02; H03H17/0248; H03H17/0261; H03H17/0263; A; A61; A61B; A61B5/00; A61B5/24; A61B5/25; A61B5/279; A61B5/28; A61B5/283; A61B5/287; A61B5/68; A61B5/6846; A61B5/6847; A61B5/6852; A61B5/6855; A61B5/6858; A61N; A61N1/00; A61N1/18; A61N1/32; A61N1/36; A61N1/362; A61N1/37; A61N1/3702; Y; Y10; Y10S; Y10S128/00; Y10S128/901
Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
117 words
An element for filtering an artifact from a composite signal comprising sample values arranged with respect to time, the element comprising means for selecting sets of WL sample values in time-sequence along the composite signal, means for arranging the WL sample values of each set into ordered positions following a predetermined permutation, means for determining the duration, AL, of the artifact in terms of the number of sample values that the artifact contains, means for selecting one of the ordered positions, z, within each permutation taking into account the artifact duration, AL, and means for generating a filter output comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the composite signal.
Claim 2
Dependent Claim
117 words
An element for filtering an artifact from a composite signal comprising sample values arranged with respect to time, the element comprising means for selecting sets of WL sample values in time-sequence along the composite signal, means for arranging the WL sample values of each set into ordered positions following a predetermined permutation, means for determining the duration, AL, of the artifact in terms of the number of sample values that the artifact contains, means for selecting one of the ordered positions, z, within each permutation taking into account the artifact duration, AL, and means for generating a filter output comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the composite signal.
Claim 3
Dependent Claim
22 words
An element according to claim 1 wherein the means for arranging orders the WL sample values in magnitude from smallest to largest.
Claim 4
Dependent Claim
21 words
An element according to claim 2 wherein the means for selecting one of the ordered positions increases z as AL decreases.
Claim 5
Dependent Claim
21 words
An element according to claim 1 wherein the means for selecting sets of WL samples selects WL taking into account AL.
Claim 6
Dependent Claim
18 words
An element according to claim 4 wherein the means for selecting sets of WL sample values sets WL>2AL.
Claim 7
Dependent Claim
20 words
An element according to claim 5 wherein the means for selecting sets of WL sample values sets WL=2AL+k where ##EQU12##
Claim 8
Dependent Claim
155 words
An element for filtering an artifact from a composite signal comprising sample values arranged with respect to time, the element comprising means for selecting a filter window encompassing a set of WL sample values within the composite signal, means for determining the duration, AL, of the artifact in terms of the number of sample values that the artifact contains, means for advancing the filter window in time sequence along the composite signal while, upon each advance, (I) arranging the WL sample values of the encompassed set into ordered positions following a predetermined permutation, (ii) selecting one of the ordered positions, z, within the permutation taking into account the artifact duration AL, and (iii) generating an output comprising the sample value occupying the ordered position, z, and means for generating a filtered signal comprising the outputs arranged with respect to time in sequence with the composite signal, the filtered signal being essentially free of the artifact.
Claim 9
Dependent Claim
155 words
An element for filtering an artifact from a composite signal comprising sample values arranged with respect to time, the element comprising means for selecting a filter window encompassing a set of WL sample values within the composite signal, means for determining the duration, AL, of the artifact in terms of the number of sample values that the artifact contains, means for advancing the filter window in time sequence along the composite signal while, upon each advance, (I) arranging the WL sample values of the encompassed set into ordered positions following a predetermined permutation, (ii) selecting one of the ordered positions, z, within the permutation taking into account the artifact duration AL, and (iii) generating an output comprising the sample value occupying the ordered position, z, and means for generating a filtered signal comprising the outputs arranged with respect to time in sequence with the composite signal, the filtered signal being essentially free of the artifact.
Claim 10
Dependent Claim
22 words
An element according to claim 7 wherein the means for arranging orders the WL sample values in magnitude from smallest to largest.
Claim 11
Dependent Claim
21 words
An element according to claim 7 wherein the means for selecting sets of WL samples selects WL taking into account AL.
Claim 12
Dependent Claim
19 words
An element according to claim 7 wherein the means for selecting sets of WL sample values sets WL>2 AL.
Claim 13
Dependent Claim
21 words
An element according to claim 7 wherein the means for selecting sets of WL sample values sets WL=2 AL+k where ##EQU13##
Claim 14
Dependent Claim
15 words
A system according to claim 7 further including means for increasing z as AL decreases.
Claim 15
Dependent Claim
177 words
A nonlinear filter for processing a signal derived from a biological event comprising sample values arranged with respect to time, the derived biological signal having an artifact signal portion and a useful signal portion, the filter comprising a derived biological signal input, means for establishing a sample window that encompasses a predetermined number of sample values X(k), where k=1 to WL, and WL varies according to the number of sample values that the artifact signal portion contains, means for advancing the sample window sequentially along the biological signal in increments of one sample value, while, upon each advance: sorting the sample values X(k) within the sample window into a permutation from the smallest to the largest sample values X(p[k]), where p[k] comprises a sort position of the permutation, selecting a sort position p[f] expressed as ##EQU14## where z is the sort position of WL positions and generating an interim output comprising the value of X(p[f]), and means for generating a filter output comprising the interim outputs arranged with respect to time in sequence with the composite signal.
Claim 16
Dependent Claim
177 words
A nonlinear filter for processing a signal derived from a biological event comprising sample values arranged with respect to time, the derived biological signal having an artifact signal portion and a useful signal portion, the filter comprising a derived biological signal input, means for establishing a sample window that encompasses a predetermined number of sample values X(k), where k=1 to WL, and WL varies according to the number of sample values that the artifact signal portion contains, means for advancing the sample window sequentially along the biological signal in increments of one sample value, while, upon each advance: sorting the sample values X(k) within the sample window into a permutation from the smallest to the largest sample values X(p[k]), where p[k] comprises a sort position of the permutation, selecting a sort position p[f] expressed as ##EQU14## where z is the sort position of WL positions and generating an interim output comprising the value of X(p[f]), and means for generating a filter output comprising the interim outputs arranged with respect to time in sequence with the composite signal.
Claim 17
Dependent Claim
28 words
A filter according to claim 13 wherein the means for establishing sets WL to at least twice the number of sample values that the artifact signal portion contains.
Claim 18
Dependent Claim
33 words
A filter according to claim 14 wherein the means for establishing sets WL so that WL exceeds twice the number of sample values that the periodic artifact signal portion contains by k, ##EQU15##
Claim 19
Dependent Claim
30 words
A filter according to claim 14 wherein the means for advancing sets f of the sort position p[f] to ##EQU16## where the expression: ##EQU17## represents the integer part of: ##EQU18##
Claim 20
Dependent Claim
76 words
A filter according to claim 14 wherein the means for generating the filter output retains a prescribed number, y 1 , of beginning sample values from the derived biological signal and a number, y 2 , of ending sample values from the derived biological signal and arranges the outputs between the prescribed number of beginning and ending sample values to keep the filter output arranged with respect to time in sequence with the derived biological signal.
Claim 21
Dependent Claim
40 words
A filter according to claim 17 wherein the means for advancing operates so that f of the sort position p[f] is expressed as ##EQU19## where z is the sort position of WL positions, and wherein y.sub.1 =z-1 and y.sub.2 =WL-z.
Claim 22
Independent Claim
120 words
A method for processing a composite signal comprising sample values arranged with respect to time, the composite signal having an artifact signal portion and a useful signal portion, the method comprising the steps of selecting sets of WL sample values in time-sequence along the composite signal, arranging the WL sample values of each set into ordered positions following a predetermined permutation, determining the duration AL of the artifact signal position in terms of the number of sample values the artifact signal position contains, selecting one of the ordered positions, z, within each permutation taking into account AL, and generating a filter output comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the composite signal.
Claim 23
Independent Claim
120 words
A method for processing a composite signal comprising sample values arranged with respect to time, the composite signal having an artifact signal portion and a useful signal portion, the method comprising the steps of selecting sets of WL sample values in time-sequence along the composite signal, arranging the WL sample values of each set into ordered positions following a predetermined permutation, determining the duration AL of the artifact signal position in terms of the number of sample values the artifact signal position contains, selecting one of the ordered positions, z, within each permutation taking into account AL, and generating a filter output comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the composite signal.
Claim 24
Dependent Claim
22 words
A method according to claim 19 further comprising the step of ordering the WL sample values in magnitude from smallest to largest.
Claim 25
Dependent Claim
16 words
A method according to claim 20 further comprising the step of increasing z as AL decreases.
Claim 26
Dependent Claim
14 words
A method according to claim 21 further comprising the step of setting WL>2 AL.
Claim 27
Dependent Claim
15 words
A method according to claim 21 further comprising the step of setting WL=2AL+k where ##EQU20##
Claim 28
Dependent Claim
18 words
A method according to claim 19 wherein the composite signal comprises a depolarization wave front in myocardial tissue.
Claim 29
Dependent Claim
15 words
A method according to claim 19 wherein the composite signal comprises body tissue biopotential morphology.
Claim 30
Dependent Claim
12 words
A method according to claim 19 wherein the composite signal comprises electroencephalograms.
Claim 31
Dependent Claim
13 words
A method according to claim 19 wherein the composite signal comprises respiratory signals.
Claim 32
Dependent Claim
12 words
A method according to claim 19 wherein the composite signal comprises electrogastrograms.
Claim 33
Dependent Claim
12 words
A method according to claim 19 wherein the composite signal comprises electromyograms.
Claim 34
Dependent Claim
112 words
An element that filters a pacing artifact from an electrogram comprising means for selecting sets of WL sample values in time-sequence along the electrogram, means for arranging the WL sample values of each set into ordered positions following a predetermined permutation, means for determining the duration AL of the artifact in terms of the number of sample values that the artifact contains means for selecting one of the ordered positions, z, within each permutation taking into account AL, and means for generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 35
Dependent Claim
112 words
An element that filters a pacing artifact from an electrogram comprising means for selecting sets of WL sample values in time-sequence along the electrogram, means for arranging the WL sample values of each set into ordered positions following a predetermined permutation, means for determining the duration AL of the artifact in terms of the number of sample values that the artifact contains means for selecting one of the ordered positions, z, within each permutation taking into account AL, and means for generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 36
Independent Claim
154 words
A system for analyzing an electrogram comprising electrode means for sensing an electrogram in myocardial tissue, pacing means for conditioning the electrode means to emit a pacing signal and to sense an electrogram as a result of the pacing signal, the electrogram including a pacing artifact having a duration AL expressed in terms of the number of sample values that the pacing artifact contains, a signal processor that filters the pacing artifact from the electrogram by steps comprising (i) selecting sets of WL sample values in time-sequence along the electrogram, (ii) arranging the WL sample values of each set into ordered positions following a predetermined permutation, (iii) selecting one of the ordered positions, z, within each permutation taking into account AL, and (iv) generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 37
Independent Claim
154 words
A system for analyzing an electrogram comprising electrode means for sensing an electrogram in myocardial tissue, pacing means for conditioning the electrode means to emit a pacing signal and to sense an electrogram as a result of the pacing signal, the electrogram including a pacing artifact having a duration AL expressed in terms of the number of sample values that the pacing artifact contains, a signal processor that filters the pacing artifact from the electrogram by steps comprising (i) selecting sets of WL sample values in time-sequence along the electrogram, (ii) arranging the WL sample values of each set into ordered positions following a predetermined permutation, (iii) selecting one of the ordered positions, z, within each permutation taking into account AL, and (iv) generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 38
Dependent Claim
17 words
A system according to claim 30 or 31 further including means for increasing z an AL decreases.
Claim 39
Dependent Claim
28 words
A system according to claim 30 or 31 wherein the means for arranging of WL sample values orders the WL sample values in magnitude from smallest to largest.
Claim 40
Dependent Claim
10 words
A system according to claim 30 or 31 wherein WL>2AL.
Claim 41
Dependent Claim
22 words
A system according to claim 30 or 31 wherein the means for selecting sets of WL sample values sets WL=2AL+k where ##EQU21##
Claim 42
Independent Claim
125 words
A method for analyzing an electrogram comprising the steps of emitting a pacing signal and sensing an electrogram as a result of the pacing signal, the electrogram including a pacing artifact, selecting sets of WL sample values in time-sequence along the electrogram, arranging the WL sample values of each set into ordered positions following a predetermined permutation, determining the duration AL of the pacing artifact in terms of the number of sample values that the artifact signal position contains, selecting one of the ordered positions, z, within each permutation taking into account AL, and generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 43
Independent Claim
125 words
A method for analyzing an electrogram comprising the steps of emitting a pacing signal and sensing an electrogram as a result of the pacing signal, the electrogram including a pacing artifact, selecting sets of WL sample values in time-sequence along the electrogram, arranging the WL sample values of each set into ordered positions following a predetermined permutation, determining the duration AL of the pacing artifact in terms of the number of sample values that the artifact signal position contains, selecting one of the ordered positions, z, within each permutation taking into account AL, and generating a filtered electrogram comprising the sample values occupying the ordered position, z, of each permutation in time-sequence with the electrogram, the filtered electrogram being essentially free of the pacing artifact.
Claim 44
Dependent Claim
22 words
A method according to claim 36 further comprising the step of ordering the WL sample values in magnitude from smallest to largest.
Claim 45
Dependent Claim
15 words
A method according to claim 36 further comprising the step of increasing as AL decreases.
Claim 46
Dependent Claim
13 words
A method according to claim 36 wherein WL is selected such that WL>2AL.
Claim 47
Dependent Claim
15 words
A method according to claim 36 wherein WL is selected such that WL=2AL+k where ##EQU22##
References Cited (Backward Citations)
US4105023A
Cited
US4149527A
Cited
US4244376A
Cited
US4868773A
Cited
US4674509A
Cited
US4723553A
Cited
US5029118A
Cited
US4793361A
Cited
US5010888A
Cited
US5436564A
Cited
US5238000A
Cited
US5168459A
Cited
US5415166A
Cited
US5267567A
Cited
US5323781A
Cited
US5273049A
Cited
US5311874A
Cited
US5324284A
Cited
US5411025A
Cited
US5311873A
Cited
US5450846A
Cited
WO1994016619A1
Cited
WO1994021165A1
Cited
US5476495A
Cited
WO1994021168A1
Cited
US5391199A
Cited
US5409000A
Cited
US5409007A
Cited
US5454370A
Cited
US5405375A
Cited
US5487391A
Cited
US5485849A
Cited
US5447519A
Cited
US5413105A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-02-11 | 2000-08-12 | 2001-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-11 | 2004-08-12 | 2005-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-11 | 2008-08-12 | 2009-02-11 | $7700.00 | Window Closed / Lapsed |